title: Role of circulating cell-free DNA levels in patients with severe preeclampsia and HELLP syndrome.
abstract: BACKGROUND
  Increased plasma levels of circulating cell-free DNA (c-f DNA) have been recently described in diseases related to ischemia and/or hypoxia. Preeclampsia (PCL) is a hypertensive disorder of pregnancy, of unknown origin, where a defective placentation resulting in placental ischemia plays an important role. HELLP syndrome (haemolysis, elevated liver enzymes, and low platelet count) is the most serious form of PCL. The origin of the disease is unknown, and there are no markers to help us to make an early diagnosis of disease or to predict patients who are at risk of suffering serious complications.
  
  
  METHODS
  We measured circulating c-f DNA levels in a group of control pregnant women (n = 20), patients with mild PCL (n = 9), patients with severe PCL (n = 24), and patients with HELLP syndrome (n = 8).
  
  
  RESULTS
  Values of circulating c-f DNA were 333.59 ± 64.3 ng/ml in control subjects; 635.11 ± 111.7 ng/ml in patients with mild PCL; 1,264.63 ± 127.1 ng/ml in patients with severe PCL, and 1,595.95 ± 269.8 ng/ml in patients with HELPP syndrome. (P < 0.0001). Values of c-f DNA >950 ng/ml had a sensitivity and specificity for detecting severe PCL and/or HELLLP syndrome of 0.71 and 0.93, respectively.
  
  
  CONCLUSIONS
  As far as we know, this is the first report of increased c-f DNA levels in HELLP syndrome. In this preliminary report, we have observed a gradual and strong relation between c-f DNA levels and range of severity of PCL, with it the highest in patients with HELLP syndrome. Further studies are needed for evaluating the utility of this technique in hypertensive disorders of pregnancy and, particularly, in HELLP syndrome.
authors.affiliation: Unidad Clínico-Experimental de Riesgo Vascular (UCERV-UCAMI del Servicio de Medicina Interna) y Unidad de Gestion de los Laboratorios Clínicos, Instituto de Biomedicina de Sevilla (IbiS), Hospital Universitario Virgen del Rocío, SAS, Universidad de Sevilla, CSIC, Sevilla, Spain.
authors.forename: Maria L
authors.initials: ML
authors.lastname: Miranda
authors.forename: Hada C
authors.initials: HC
authors.lastname: Macher
authors.forename: Rocio
authors.initials: R
authors.lastname: Muñoz-Hernández
authors.forename: Antonio
authors.initials: A
authors.lastname: Vallejo-Vaz
authors.forename: Rafael
authors.initials: R
authors.lastname: Moreno-Luna
authors.forename: Jose
authors.initials: J
authors.lastname: Villar
authors.forename: Juan M
authors.initials: JM
authors.lastname: Guerrero
authors.forename: Pablo
authors.initials: P
authors.lastname: Stiefel
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D002474:Cell-Free System / Q000378:metabolism; D004247:DNA / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D017359:HELLP Syndrome / Q000097:blood / Q000175:diagnosis* / Q000378:metabolism; D006771:Hospitals, Maternity; D006801:Humans; D011225:Pre-Eclampsia / Q000097:blood / Q000175:diagnosis* / Q000378:metabolism; D011237:Predictive Value of Tests; D011247:Pregnancy; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D004247:DNA
keywords: HELLP syndrome; blood pressure; hypertension; hypertension in pregnancy; hypertensive disorders of pregnancy; preeclampsia.